I just purchased a 2009 fatboy. It has rush slipon mufflers and stock everything else. I want to add an Arlen Ness big sucker air filter. My question is, do I need to add a tuner such as a SERT? The dealer said the ECM with automatically adjust with this upgrade just as it did with the muffler upgrade, is this true? If I need a tuner which one is the most perferred? I was/am leaning towards the SERT.

 

I think u can find everything u want right hear?https://www.hdforums.com/forum/searc...archid=7841678
Add yes u need a tuner with that set up

 

The dealer is mistaken, the ECM does not do anything automatically.

 

Thanks Book it, I'll check the threads out.

Troupe - Didnt think that was right.